HOW DIRECT CURRENT IN PRODUCED AND ALSO ITS WORKING

Dear student

DC or direct current is produced by DC generators and by batteries also.

Batteries undergo electrochemical reactions to produce direct current.

Electric DC generators are based on the principle of electromagnetic induction. When a conducting loop is moved in a magnetic field, electric current is induced in the loop.

An armature consists of many turns of a coil placed between the poles of a strong magnet.

The ends of the coil are connected to a split-ring commutator R₁ and R₂. Two carbon brushes B₁ and B₂ press lightly against the two halves of the commutator

Working:

1. Armature ABCD is rotated in anti clockwise direction inside the magnetic field.
2. Applying Fleming's right hand rule to arm AB (moving downwards), (fig a) the direction of the induced current is found to be upwards (along AB).
3. Applying Fleming right hand rule to the arm CD (moving upwards) the direction of the induced current is found to be downwards (along CD)
4. For the half rotation of the armature hence the direction of the induced current in the armature is clockwise i.e. ABCD B₂R B₁ A.
5. Similarly for the next half rotation of the armature (fig b) applying Fleming's RH rule gives the direction of induced current to be again clockwise i.e, DCBAB₂RB₁D.
6. Thus during the entire rotation, the current through load resistor R remains the same. The nature of the current produced is hence dc (direct current).

 

 

We hope that clarifies your query.

 

Regards

Team

Topperlearning